The U.S. military says a roadside bomb killed two U.S. Marines Saturday in Afghanistan's volatile south, where U.S. and British troops continue their offensive to oust Taliban insurgents from the region.

Military officials initially reported four U.S. Marines had died in the attack in Helmand province, but they later corrected the figure, saying the same incident had been reported twice by mistake.

A third U.S. soldier serving with NATO-led forces in the south died Friday from wounds received in combat last month.

The U.S. deaths came a day after eight British soldiers were killed in Helmand in a 24-hour period.

More than 190 foreign troops have died in Afghanistan this year, which is on pace to be the deadliest since U.S.-led forces ousted the Taliban from power in late 2001.